UV工艺降解阿特拉津机理及对DBPFP的影响规律

对不同UV光氧化工艺降解水溶液中阿特拉津（ATZ）的动力学和机理，以及对后续氯化处理过程中溶液需氯量和消毒副产物生成势（DBPFP）的影响规律与机理进行了系统研究.结果表明，ATZ在不同UV光氧化工艺中的降解均符合准一级反应动力学.ATZ在单独UV辐照工艺中的去除效率相对较低；UV/H₂O₂工艺对ATZ具有相对较高的去除效率，且其去除率随H₂O₂浓度的增大呈现出先增加后降低的变化趋势；UV/TiO₂工艺降解去除ATZ的效率较单独UV辐照和UV/H₂O₂工艺低，ATZ在UV/TiO₂工艺中的降解与溶液透光率和氧化活性物种（ROS）生成量存在直接关系；UV/H₂O₂/TiO₂工艺中，ATZ的降解速率较UV/TiO₂工艺有所提高.ATZ水溶液经不同UV光氧化工艺预处理和氯化处理后，均检出了5种消毒副产物（DBPs），其中三氯甲烷（TCM）和三氯丙酮（TCP）为主要氯化DBPs.本研究表明，在不同UV光氧化预处理过程中，ATZ具有不同的降解路径，进而对ATZ水溶液在后续氯化过程中的DBPPF产生显著影响.

Ultraviolet photooxidation of atrazine and its effect on disinfection by-product formation potential

The degradation kinetics and mechanisms of atrazine (ATZ) in aqueous solution by various UV photooxidation processes, as well as its influence on chlorine demand and disinfection by-product formation potential (DBPFP) in the subsequent chlorination process were systematically investigated. The results showed that the degradation of ATZ in different photooxidation processes followed the pseudo-first-order reaction kinetics. In comparison with low removal efficiency of ATZ by UV irradiation alone, the UV/H₂O₂ process had much higher removal efficiency, and it first increases and then decreases with increasing H₂O₂ concentration. In UV/TiO₂ process, the degradation of ATZ was directly related to the production of oxidizing active species (ROS) such as holes, ·OH and ·O₂^-. In UV/H₂O₂/TiO₂ process, the degradation rate of ATZ was found higher than that in the UV/TiO₂ process. After UV pretreatment and the following chlorination, five disinfection by-products (DBPs) were detected in ATZ aqueous solution. Among of them, chloroform (TCM) and trichloroacetone (TCP) were the major chlorinated DBPs. The present study showed that the degradation of ATZ followed different degradation pathways in different UV photooxidation pretreatment processes, which would significantly affect the disinfection by-product formation potential (DBPPF) of ATZ solution in the following chlorination process.